Lifting jack



s sheets-sheet May 21, 1929. .-w. a; LAKE LIFTING JACK Filed sept. "7. 192e- May 219 B.' LAKE I LIFTING JAcx 'mea sept. 7, A1926 l 3 SheetsSheet 2 www drijf W. B. LAKE LIFTING JACK Filed Sept. 7, 1926 May 21, i929.

3 Sheets-Sheet 3 Patented'May 21, 1929.` UNITED `STATES PATENT. orrica;

WILLIAM aman Lum, or nnanrraimymremn.

I Lmma Jack.

Application led September 7, 1928, Serial No. 134,081, and in Great Britain Augult`24, 1928.

This invention'relates to improvements in lifting jacks Y The object of this invention is to provide a hydraulic jack which will have a high or double lift so that it will be suitable for use on vehicles iitted with balloon or over-sized said jack being either of the garage type or 1 of the ordinary road.

With these and other objects in View, the invention consists in providing a hydraulic lifting jack which is adapted to be raised through the medium of a reciprocating pump rod or like means and lowered by the rotation or partial rotation of the said pump rod or ike means.

The invention further consists in providingin a hydraulic jack a 'single valve which is adapted to control the raising and also the lowering of the jack.

Tlieinvention will now be described with reference to the accompanying drawings, in which Figure 1 is a longitudinal sectional elevatype suitable for use on the tion of one form of jack constructed according to this invention and suitable for garage use' Figure 2 is a sectional plan thereof;

Figure 3 is a cross section taken on the line a--a of Figure 1;

Figure 4 is a cross section taken on the line -b of Figure l; Figure 5 is an enlarged sectional elevation of the upper portion of the jack casing showing the. lower end of one of the p ungers therein;

Figure 6 is an enlarged sectional elevation showing the co-operating means of the 1nner and outer plungers;

Figure 7 is an enlarged longitudinal sectional elevation of the valve and plunger, 'showing the plunger in use, the valve being in position for the liftingoperation;

Figure 8 isa similar view to Figure 7 showing the valve operating means in use during the lowering operation; y

Figure 9 is a sectional elevation of a modilied form of hydraulic jack, suitable for ordinary use and for carrying on a car;

Figure 10 is a plan thereof;

section taken on v the As shown, more particularly in Figures l to 8, a pair of telescopic plunger members 1 and 2 are mounted in a cylinder 3 formed in a casing 4 'which contains an oil or like reservoir 5 from which oil is adapted to pass to the cylinder 3 by way of a. valve 6. The casing 4 is provided with wheels 7 which are rotatably mounted and carried by a bracket 8 prefen ably formed integrally with the said casing 4. To the sides of the casing 4 are pivotally mounted at 9 a pair of bracket-like supports 10 which are maintained in their adjusted position by springs or the like 11. In Figure 2 one bracket 10 is shown in its outwardly extended position and the other bracket 10 is shown folded back on the casing 4 so that the jack can be positioned adjacent tothe wheel of the vehicle it is desired to lift. Withinthe casing 4 is mounted a tubular member 12. This tubular member 12 is adapted to screw into a sleeve or the like 13 which carries the va'lve 6. This sleeve or the like 13 is mounted in a bore formed in an extension 14 of the wall. of the cylinder 3. The valve end of the sleeve 13 is positioned within an enlarged bore arranged adjacent to the lower end of the cylinder 3 and is threaded for the reception of a threaded closure member 15 which is formed with apertures 16. This closure member 15 is adapted to form an adjustable abutment for a spring 17 which is adapted to act on the valve 6 and maintain it on its seating. A suitable i gauze screen is positioned in front of the apertures 16 of the member 15. The stem 18 of the valve 6 is referably of triangular shape and is adapted) vto permit of the passage of the oil and a screen to move in a circular bore to p permit of the ingress and egress of oil. The

- of square or other angular shape in cross section and is adapted to project within a similar shaped bore 25 formed in a plunger rod 26 Y member lowered. The crutch 28 is formed with apertures This reservoir which is adapted to reciprocate and rotate within the tubular member 12. This tubular member .1,2 is formed with a flange 27 which is arranged within a gland 2 8 threadedly mounted in the easing 4. On the flange 27 is arranged a cup-leather or like washer 29 and on this washer 29 is mounted a metal washer 30. The arrangement is such that leaka-ge of oil will be prevented during the forward movement of the plunger 26. On the washer 30 is adapted to seat one end of a spring 31 which has its other end seated in a V-shaped washer 32 and abutting upon this washer 32 is a metal washer 33 which is adapted to bear against another cup-leather washer 34 mounted in the gland 28. This latter washer 34 is adapted to prevent the intake of air during the movementv of the plunger 26. 'lhe gland 35 to permit of oil from the oil reservoir 5. 5 is adapted to be filledfwith oil through the aperture in the casing 4. This aperture is closed by a screw-threaded cap 36 formed with an air vent or the like 37. The lower end of the plunger 1 is fitted with a cupleather washer or the like 38 which is maintained in position by a nut member or the like 39 screwed on to a threaded extension of the plunger 1; Adjacent to the lower end of the plunger 1 is cut a groove 40 within which is arranged a split expansion ring 41. When the plunger 1 is in its highest position, this the passage of ring 41 expands and enters an annular groove' 42 cut in the outer plunger member 2 and it will be seen that this arrangement prevents the member 1 being forced out of the plunger 2. The lower wall of the annular groove 42 is cut away or inclined at 43 so as to contract the expansion ring 41 and permit the downward movement of the plunger 1 when the weight carried by the crutch head 44 is head 44 is preferably adjustably mounted in the plunger 1 in the well-known manner, the adjustment being effected by means of a pin 45 adapted to be positioned in one of a plurailty of apertures 46 formed in a rod 47 carried by the crutch head 44, the pin 45'being arranged transversely and adapted to seat on the upper end' of the plunger 1 A suitable washer 48 is arranged on the upper end of the plunger 2 to further prevent leakage between the plungers 1 and 2. The lower end of the plunger member 2 is also formed with an annular groove 49 which is cut away or inclined at 50 in a similar manner to the groove 42.. Within this groove 49 is adapted to be positioned a split ring 51 when the plunger 2 is in its highest position and thus limit the outward movement of the 'will be seen that bytarrangmg plunger 2. The split ring 51 is normally arranged within a groove 52 cut in the cylinder 3 and the arrangement is such that the split ring 51 will be expanded and lie in the groove y 52 when the plunger 2 is lowered by the weight carried by the crutch head 44.. The upper end of the cylinder 3 is maintained oiltight by washers 53 and a threaded member 54 screwed into the said upper end of the cylinder 3. An oil leak 55 is provided for the rel turn of any oil to the reservoir 5 which may have passed by the lower washer 53. Thus it the packing washers in the casing 3 and in the inner telescopic member 1, the said telescopic members may be raised to a maximum height to give considerably greater lift than heretofore.

To the outer end of the pump rod 26 is pivoted at 56 a connecting rod member 57 which is rotatably mounted in a block 57a. This.

block or the like 57, which carries an extension 57b of the connecting rod member 57, is fitted with a pair of screws or nut members 7 0 which are 'freely mounted in apertures 58a cut in forked arms of the lower bifurcated or forked end 58 of an operating lever 59, which is f ulcrumed on a fulcrum pm 60. This fulcrum pin 60 is carried in a forked bracket 61 which is adapted to form a base for the operating lever 59. This forked bracket 61 is secured to the vouter end of a member 62 which is connected at its other end to the casing 4. Thus the fulcrum portion of the jack is maintained rigidly in spaced relation to the casing portion of the jack. The lever 59 is preferably provided with an auxiliary fulcrum 63 and is so arranged that it may be adjusted in an angular position. For instance, the lever 59 may be arranged in its normally vertical position by placing a pin-64 through an aperture 65 cut in a plate 66 carried by the fulcrum 58, or it may be arranged in an inclined position by placing the pin 64 through the aperture in the lever 59, and through an aperture 67 in the plate 66, when it is inconvenient for the lever 59 to be in a normally vertical position such as when the jack .has to be positioned a considerable distance underthe ear.

The upwardmovement of the lever 59 is limited by a plate 68 which is secured to the forked brackets 61, and adapted to engage the forked end 58 of the .operating lever 59. To the outer end of the connecting rod 57 which is rotatably be seen that by ropositioned under, for instance, an axle of a vehicle it is desired to lift and the operating lever 59 is in a vertical sition, the said lever 59 is moved downwardlto force the lunger 26 into the tubular member 12. It wi l be obvious that by reciprocating the plunger 26 through the medium of the operating lever 59 oil from the reservoir will be forced past the valve 6 into the cylinder 3 by way of the aperture 23 in the threaded member 21 and apertures 19 in the sleeve 13. During this operation the oil will beV drawn in from the reservoir 5 by way'of the ports 35 and will be i v forced into the cylinder 3 to raise the plungers 1 and 2 and the crutch head 44. Whe'n the plungersl are full raised the split rin 41 in the plunger 1 wi l expand and enter e annular groove 42 cut in the outer plunger 2 and the split ring 51 normally posltionedfin the groove 52 of the cylinder 3 will contract and enter the groove 49 cut in the outer plunger 2. When it is desired to lower the jack the operating lever. 59 is returned to its normal vertical position and the handle member 69 is turned to partially rotate the plunger 26. This partial rotation of the plunger 26 will also rotate the rod 22 and turn the threaded end 21 in the sleeve 13-and thus the forward end of the rod 22 will engage on the valve stem 18 and force the valve 6 olf its' seating against the action of the ,spring 17. The oil in the cylinder 3 will now return by way of the ports 23 and 35 and the tubular member 12 to the reservoir 5." The lowering speed of the jack can be varied according tothe amount the valve 6 is moved olf itsseating and the lowering willbe assisted by the wei ht carried by the crutch head 44. When t e lowering operation is completed the handle 69 is turned back to its normal position so as to permit the valve 6 to function in .the usual manner. The first outward or downward movement of the operating lever 59 will obviously create a vacuum in the tubular member 12 until the oil can flow from the reservoir 5 through the port 35. The forward move'- ment of the plun er will force the oil past the valve 6 into -t e cylinder 3 and the sequence of operations will be repeated when it is required to again use the jack. The wheels 7 on the forward end of the jack will assist the positioning of the jack under the car and it will be seen that the jack will be adequately supported when one or both of the brackets 10 are in their outward position.

In a modified construction as shown in Figures 9 to 13, and when the invention is aplied' to a jack suitable for ordina use and or carrying on a ycar,vthe casin 4 1s formed with a bifurcated bracket 71 which is adapted to carry a fulcrum pin 72 on which is mounted a handle socket 73. ,This operatin handle socket 73 is formed with 'a pair o downwardly extending arms :74 on which are will not be further described as the construction and operation is similar to the previous construction. lfVith'in the socket 73 is adapted to be laced the lower end of an o erating handle 7 of an suitable length. T e lower end operating li' or provided with a bayonet joint or fitting 78 which is adapted to co-operate witha bayonet fitting 79 formed or rovided in the interior of the socket 73. The arrangement is such that when the handle 77 is forced into Vthe socket 73 and given a partial rotation, the said handle 77 will be detachably locked in position in the co-operating' bayonet fittin s by theaction of a spring 80 disposed within a recess formed in the lower end of the said socket 73. The extreme lower end of the handle or lever 77 is formed with another bayonet socket fitting 81 which is adapted to co-operate. with a socket pin fitting 82 secured on the outer end of the plunger rod 26. A

' In operation, and when it is desired to raise this modified form of jack, the casing 4 is positioned under the vehicle and the crutch ead 44 is arranged under the portion vof the vehicle to be lifted. v The operating handle lever 77 is pushed into the handle socket 73 'against the action of the spring 80 and partially rotated so that the bayonet fittin s 8 and 79 co-operate to hold the handle 77 1n andle or lever 77 is formed position. U on the downward andupward movement o the handle 77 the plunger 26 will be reciprocated through the medium of the links 75 and arms 74 and thus the oil will be forced from the reservoir 5 past the valve y6 into the cylinder 3 to raise the plunger members 1 and 2 in a manner similar to that described inthe previous construction. A suitable stop 83 is provided on the bracket 71 to co-operate with a squared end 84 formed ftments 8 and 79 and per- 77 is now inserted in the socket in fitting 82 y on the plunger rod 26 and partlally rotated to rotate the plunger rod 26. This rotation of the plun er rod 26 will act in a similar v manner to t at previously described in connection with the first construction and move the valve 6 of its seating and thus the weight carried by the crutch head 44 will be lowered automatically. In this modified construction, the'wheels 7 and supporting brackets l() are omitted, but it will be understood that they may be provided if desired.

It will be seen that by the invention there is provided a hydraulic jack for garage or ordinary use which will have a higherlift than is obtained by hydraulic jacks at present constructed and further the lift may be increased by providing more than two telescopic members.

Reference is made to applicants co-pending application filed September 8, 1926, Serial No. 134,227, for claims directed to subjectmatter specifically described but not claimed herein.

What I claim is 1. A lifting jack of the hydraulic type including a load lifter, a pump rod, hydraulic means to exert a raising force on the .load lifter by reciprocating the pump rod, and

means to relieve the load lifter of such force v by rotative operation of the pump rod.

2. A lifting jack'of `the hydraulic type including a load lifter, fluid pressure means whereby the load lifter may be raised or lowered, and a single valve intermediate the fluid pressure means and load lifter, said valve being freely responsive to fluid pressur-e to admit the fluid under pressure to the' load lifter and adapted for operation by the fluid pressure means to relieve the load lifter of the fluid pressure.

3. A liftino` 'ack ofthe hydraulic type including a load lifter, a motive fluid reservoir, a pump rod for directing a motive fluid from said reservoir to raise the load lifter, a lever for reciprocating said rod to raise the load lifter, and means responsive to a rotation of said pump rod to relieve the load lifter of the sustaining pressure of said motive fluid.

4. In a hydraulic jack, a load support, a pump rod for directing a motive fluid from a suitable source to and beneath said support lfor raising the same, a valve opening under the pressure of the motive fluid responsive to pump rod movement to permit the passage of the motive fluid to the load support, a valve rod adapted in rotation in one direction to engageand open the valve, said pump rod being mounted for rotation to similarly operatethe valve rodL whereby rotation of the pump rod will rotate the valve rod to open the valve for relieving the pressure beneath the load support.

5. In a hydraulic lifting jack, a lifting plunger, means for pumping a fluid to and beneath the plunger to raise the same, said means including a reciprocating pump rod and a valve opening under the pressure of the fluid incident to the operation of the pump rod, a valve rod connected to the valve and adapted in movement to open the valve, and means whereby the pump rod may be independently actuated to operate the valve 'tative movement to open the valve,

rod to thereby relieve the fluid pressure beneath the plunger. v` A 6. A hydrauliclifting jack, a lifting plunger, means for'pumping a motive fluid beneath said plunger, said means including a reciprocating pump rod and a valve past which the fluid is pumped, a valve rod adapted in rothe valve rod andpump rod being connected for relative sliding movement Without permitting a relative rotary movement, and means Whereby the pump rod may be rotated at will to operate the valve rod.

7. A hydraulic lifting jack including a plunger to be operated b the pressure of a motive fluid, a pump for irectin the' motive fluid under pressure beneath t e plunger, said pump including a pump rod adapted for reciprocating movement and a valve to normally prevent return of such fluid from beneath the plunger, a valve rod for operating the .valve independent of the fluid pressure, said valve rod being non-circular in cross sec tion and slidingly fitting a correspondingly shaped bore in the pump rod, and means whereby the pump rod may be rotated to correspondingly actuate the valve rod.

4 8. A lifting jack of hydraulic type comprising a casing having a reservoir, a cylinder, a tubular-member intermediate the reservoir and cylinder, a pair of telescopic members slidably mounted in the cylinder, a valve positioned adjacet to the lower end of the cylinder to close the end of the tubular member, a pump rod adapted to reciprocate in the tubular member, an operating lever connected to said pump rod, a sleeve arranged in the tubular member and carrying said valve, an angular shaped rod formed with athread to cooperate with a thread formed in said sleeve, the pump rod being formed witha bere corresponding in size and shape to the sectional dimensions of the angular rod to insure rotative movement of the angular rod in the rotative movement of the pump rod, and spring means for maintaining the valve on its seat.

9. A lifting jack as claimed in claim 8,

wherein the pump rod sleeve is threaded in the casing and provided with washers and a spring to space the said washers which are adapted to prevent leakage of oil during the reciprocation of the piston rod, said sleeve being formed with apertures communicating with the reservoirand the tubular member.

10. A lifting jack as claimed in claim 8, wherein the operating lever is formed with a forked end in which a connecting rod is mounted for rotary motion, said connecting rod having a handle at one end and being connected at its other end to the reciprocating plunger, means being provided to limit the movement of the operatmg lever.

11. A lifting jack as claimed in claim 8, wherein the operating lever is formed with an auxiliary fulcrum and means are provided for the angular adjustment of the sald operating lever about the said fulcrum.

12. A lifting jack as claimed in claim 8, 5 wherein the casing is fitted with a..pivoted sleeve member formed with depending arms connected ly links to the reciprocating (Plunger rod, sai sleeve having means to etachabl lock a lever or peratin handle therein, said plunger rod being also tted with means 10 for detachably locking the lever or operating handle therein.

. In testimony vwhereof I have hereunto signed my name. l

. WILLIAM BEARD LAKE. 

